Detailed Description
The illustrations and descriptions presented herein are intended to familiarize others skilled in the art with the present invention, its principles, and its practical application. The specific embodiments of the disclosure as set forth are not intended to be exhaustive or to limit the scope of the disclosure.
One or more as used herein means that at least one or more of the listed components can be used as disclosed. It should be understood that the functionality of any ingredient or component may be an average functionality due to imperfections in the raw materials, incomplete conversion of reactants, and formation of byproducts.
The article is comprised of a thermoset polymer having a dye sublimation image in a layer attached to or integral with a surface of the thermoset polymer, wherein at least a portion of the thermoset is a foam. The thermoset may be any suitable thermoset such as those known in the art. Illustratively, the thermoset may be composed of one or more crosslinked polymers, such as polyesters, polyurethanes, polyisocyanurates, polyureas, polyurea/urethanes, phenol-formaldehyde, urea-formaldehyde, melamine, diallyl phthalate, epoxy resins, epoxy-novolacs, benzoxazines, polyimides, bismaleimides, cyanate esters, furan resins, or silicones. Desirably, the thermoset is a polyurethane, polyisocyanurate, polyurea, or combination thereof.
Fig. 1 is a schematic representation of one embodiment of the present invention wherein an article 10 is comprised of a thermoset polymer foam 20 having an adjoining layer 30, an image receiving layer 40 sandwiched between the adjoining layer 30 and a cover layer 50. The image receptive layer has a dye sublimation image in at least a portion of the thickness of the layer, as will be described further below.
At least a portion of the thermosetting polymer is a foam. Foam refers to a porous body, as is generally understood in the art. By porous (foam) is meant herein that the polymer body has a significantly reduced apparent density compared to the density of the polymer without any voids, and that the body consists of closed or open cells. Closed cell means that the gas within the cell is isolated from another cell by the polymer wall forming the cell. By open cell is meant that the gas in the cell is not so limited and is able to flow to another cell without flowing to the atmosphere through any of the polymer cell walls. The thermoset may be entirely foam, but in many cases may consist of a skin that is a dense thermoset, as is common when manufacturing polyurethane foam where desired. The foam portion may be uniform or have one or more gradients of porosity (e.g., a more porous interior and a denser surface). Typically, at least about 10%, 20%, 50%, 75% to 99%, 95% or 90% of the thermoset is foam. The skin may be of any useful thickness. Generally, the skin thickness or receiving layer 40 may be about 10 microns, 100 microns, or 500 microns to about 5 millimeters, 2 millimeters, or 1 millimeter. The skin may encapsulate any portion of the thermoset polymer foam, including the entire foam. Typically, the skin (when present) covers at least 50%, 75%, 90% or substantially the entire surface of the foam.
It may be useful for the thermoset polymer to have a layer adhered to a portion or all of the foamed thermoset polymer, for example, to facilitate the formation of dye sublimation images (e.g., image receiving layer 40), to provide a base color coating, or to provide some other characteristic (e.g., to smooth open cell surfaces on the surface of the foamed surface). Image receptive layer 40 may be a thermoplastic or thermoset polymer. The image receptive 40 layer may have similar chemical properties, such as polyurethane foam coated with polyurethane films of different coating chemistries, that may be used to form specific desired properties (e.g., abrasion and scratch resistance, uv resistance, etc.) of the dye sublimation images formed within the coating. Exemplary films or coatings may include any film, coating, or layer suitable for receiving and forming dye sublimation images, such as those known in the art. Generally, such coatings or layers may include thermosetting or thermoplastic polymers having one or more polar groups, such as polycondensates. Exemplary coatings or layers include polyurethane (e.g., oil or water dispersed dispersion of polyurethane, polyurea, or polyisocyanurate particles that coalesce to form a slightly uniform, non-porous coating upon removal of the liquid dispersion medium), epoxy, acrylic/acrylate, alkyd, polyamine, polyamide, fluoropolymer, polyvinyl fluoride, polybutylene terephthalate, polyester (e.g., polyethylene terephthalate), polycarbonate, polystyrene, and polystyrene copolymer (ABS, "acrylonitrile butadiene styrene," etc.), mixtures or combinations thereof. The image receiving layer may be smooth or have embossments or corrugations applied to it intentionally in order to aesthetic or improve traction, such as on the deck surface.
Examples of polymers that may be used in image receiving layer 40 may also include two-part acrylic-aliphatic polyurethane coatings available under the trade name PITTHANE, HPC high gloss epoxy, PPG floor concrete epoxy primers, each from PPG Industries. Examples of thermoplastic polymers that may be useful include acrylic-polyvinyl chloride copolymers available from SEKISU KYDEX of holland, michigan under the trade name KYDEX, polycarbonates available under the trade name LEXAN, and polyetherimides available from Sabic of Pi Ci fild, massachusetts under the trade name ULTEM, and polyamides available from Nylene Polymer Solutions under the trade name nylon, RILSAN from archema, and UBE America inc. Other thermoplastic polymers that may be used in the image-receiving layer include, for example, polyamides, polyimides, polyamideimides, polyesters, polyetheresters, thermoplastic polyurethanes, polyacrylates, polyacrylic acids, functionalized polyolefins (e.g., maleic anhydride grafted polyethylene), or mixtures or combinations of any of the foregoing.
The thermoset foam 20 may have a primer layer (contiguous or abutting layer 30) sandwiched between the thermoset foam and the image-receiving layer that provides one or more desired properties, such as heat resistance, to facilitate the formation of dye sublimation images attached to or integral with the thermoplastic foam. For example, the primer layer can be any useful heat resistant or endothermic coating that can aid in forming dye sublimation images without deforming or degrading the properties of the thermoset foam. The high temperature resistant coating may be any suitable high temperature coating, such as those known in the art, and typically has a relatively high use temperature (e.g., melts or degrades at a temperature higher than the thermoset polymer foam). Typically, these coatings have a high concentration of metal or inorganic particles that provide heat resistance, thermal insulation, or heat absorption, or may be high temperature foams (e.g., inorganic siliceous foams). Examples of useful heat resistant coatings include those available from PPG under the trade names PPG HI-TEMP, AMERCOAT, AMERLOCK, DIMETCOTE, PSX and SIGMATHERM. In some cases, these coatings may also be used as layers that receive dye sublimation images as described above. The primer layer may be of any useful thickness, such as those described for image receptive layer 40.
Thermoset foam 30 may have a cover layer 50 on top of the image receiving layer, which may be a clear coat or have a matte finish. The transparent or opaque coating may be smooth, textured or embossed. Texture or embossing may be desirable, such as wood grain, stone, tile, brick, or other masonry pattern. The cover layer 50 may be any useful thickness, such as described with respect to the image receptive layer. Exemplary polymers that can be used for such cover layers include those described above for the image receptive layer.
The thermoset foam 30 can have any number of open or closed cells. Even so, the holes may be advantageously closed, for example to provide improved insulation, such as siding or rigidity. The amount of closed cells may vary from substantially zero to substantially all closed cells. Typically, the amount of closed cells is less than 95%, 90%, 75% to 5%, 10% or 25%. The amount of closure or pore size can be determined by ASTM D2856.
The pore size may be any useful size for making the article 10 and may depend on the particular article and its use. Illustratively, the foam may be cellular to a cell size on the order of millimeters or even larger. Desirably, the average pore size is about 1 micron, 10 microns, 100 microns, 250 microns, 500 microns to about 10 millimeters, 5 millimeters, or 2 millimeters. The porosity may be of any shape or morphology, such as oval or spherical. If desired, the pores may be elongated by mechanical agitation (such as shearing) to achieve anisotropic properties to produce the desired shape. The average cell size can be determined as described in known image analysis techniques of photomicrographs of U.S. patent No. 5,912,729 and foam cross-sections, which can also be used to determine gradient structure.
The thermoset polymer may be rigid or flexible, but in general, it is desirable that the thermoset foam be rigid. Rigid in this context means that the thermoset will not deform under its own weight or under typical pressures used to form dye sublimation images on the thermoset. Desirably, the thermoset has a modulus of elasticity (i.e., modulus of elasticity) of at least about 5,000 pounds per square inch (psi), 10,000psi, 50,000psi, 100,000psi, 200,000psi to about 1,000,000psi, or 500,000 psi.
Thermosetting polymers may also be composed of reinforcing agents or components to achieve desired mechanical properties that may be isotropic or anisotropic. Reinforcement may also be desirable to promote the ability of the thermoset to withstand the conditions required to form a dye sublimation image. The reinforcing component may be any suitable reinforcing component that enhances or achieves the desired properties (such as stiffness, thermal conductivity, strength, heat resistance, etc.). The reinforcing component may be any suitable reinforcing component, such as those known to be useful in organic polymers. Illustratively, the reinforcing component may be a metal, ceramic, or other organic polymer (e.g., a polymer fiber, such as an engineering plastic fiber). The reinforcing component may be an inorganic compound. The reinforcing component may be particles, fibers, sheets, honeycombs, rods, or combinations thereof. The sheet may be a woven or nonwoven fibrous fabric or sheet. Desirably, the reinforcing component is a fiber, a particle, or a combination thereof.
When the reinforcing component is a fiber, it can be any useful fiber, such as an inorganic glass fiber, an engineering plastic fiber (e.g., polyamide, polyimide, polycarbonate, etc.), a carbon fiber, a natural or plant-based fiber, a metal fiber or wire, or a combination thereof, including, for example, a polymer-coated metal, carbon fiber, or inorganic glass fiber. The fibers may be long fibers or chopped fibers. Long fibers generally refer to fibers that traverse a substantial distance in one or more dimensions of the thermoset or article (typically, long fibers are at least about 5 or 10mm, and chopped fibers are less than the length). Typically, the fibers or wires may have any useful cross-sectional shape, such as square, rectangular, oval, spherical, or other polygonal shape (e.g., hexagonal, parallelogram, triangular, etc.). Typically, the average diameter of the fibers is between 1 micron, 5 microns, 10 microns, or 20 microns to about 2 millimeters, 1 millimeter, 0.5 millimeter, 250 microns, or 100 microns. The fibers are desirably inorganic fibers such as those known in the art. Illustratively, the inorganic fibers may be any E, A, C, ECR, R, S, D or NE glass fibers, such as those available from Owen-Corning.
When the reinforcing component is a microparticle, the microparticle may be any suitable particle, such as those known in the art. Illustratively, the particulates may be ceramic, organic (e.g., cellulose particles of vegetable origin such as flour), metal, or carbon particulates (e.g., carbon black, carbon nanotubes, graphite). Examples of particles that may be suitable include inorganic particles such as clay, talc, wollastonite, mica, coal ash, calcium carbonate, single metal oxides (e.g., silica, calcium oxide, titanium dioxide, aluminum oxide, zirconium oxide, or magnesium oxide) or mixed metal oxides (e.g., aluminosilicates), nitrides (silicon nitride, aluminum nitride), carbides (e.g., silicon carbide or boron carbide), or any combination (e.g., carbon oxides or nitrogen oxides) or mixtures thereof.
The enhancing component may be present in any useful amount to achieve the desired properties or to promote the ability to withstand dye sublimation image forming conditions. The amount of reinforcing component may be about 1%, 2%, 5%, 10%, 20%, 30%, 40%, 50% to about 80%, 70% or 60% by weight of the thermoset or article. The reinforcing component may be uniformly distributed throughout the thermoset or may vary within or on the thermoset. For example, the reinforcing component may be distributed on a surface such as a fibrous fabric sheet. An example of such a reinforcement is in U.S. patent No. 3,230,995;3,544,417;5,462,623;5,589,243;5,798,160;6,740,381; and 9,091,067, each of which is incorporated herein by reference. Foamed thermosets for use in the present invention may include foamed composite boards available from General Plastics Manufacturing Company (tacoma, washington) under the trade name LAST-a-FOAM; and glass fiber reinforced composite rigid polyurethane foam boards available from Coosa Composites (pelehum, alabama) and Kayco Composites llc (gland Mei Lishi, texas).
The particulate reinforcing component may be isotropic and/or anisotropic. The particulate reinforcing component may be spherical or angular (such as formed when crushing ceramic). The particulate reinforcing component may have a needle-like morphology, wherein the aspect ratio is at least 2 to 50, wherein needle-like is referred to herein as morphology that may be needle-like or platy. Needle-like means having two smaller equal dimensions (typically referred to as height and width) and one larger dimension (typically referred to as length or width). Plate-like means having two larger, slightly equal dimensions (typically width and length) and one smaller dimension (typically height). More preferably, the aspect ratio is at least 3, 4 or 5 to 25, 20 or 15. The average aspect ratio is determined by photomicrograph techniques measuring the longest and shortest dimensions of a random representative sample of particles (e.g., 100 to 200 particles).
The particle size enhancing component needs to have a useful size that cannot be too large (e.g., spanning the smallest dimension of the desired article) nor too small to achieve the desired effect on performance. In defining the available sizes, the particle sizes and size distributions are given by the median size (D50), D10, D90 and maximum size limits. The size is the equivalent sphere diameter by volume as measured by a laser scattering method (rayleigh or mie, with mie scattering preferred) using the dispersion of solids in a low solids loaded liquid. D10 is the size of 10% of the particles having the smaller size, D50 (median) is the size of 50% of the particles having the smaller size, and D90 is the size of 90% of the particles having the smaller size, by volume. The size of the particles within the thermoset can also be determined by known photomicrography techniques. Typically, the filler has an equivalent spherical median (D50) particle size of 0.1 to 25 microns, a D10 of 0.05 to 5 microns, a D90 of 20 to 40 microns, and is substantially free of particles greater than about 70 microns or even 50 micronsAnd no particles smaller than about 0.01 microns. Desirably, the median value is 5 to 10 microns, D10 is 0.5 to 2 microns, and D90 is 20 to 30 microns. Also, the reinforcing particles desirably have a particle size of 0.1m2 /g to 20m2 /g and preferably 2m2 /g to 10m2 The specific surface area per gram can be determined by known standard methods such as nitrogen absorption, typically referred to as BET nitrogen absorption.
The thermosetting polymer may be a polyurethane rigid foam, a polyisocyanurate rigid foam, a polyurea rigid foam, or a combination thereof, such as those known in the art. Description of such rigid foams is given by EP0903368 and U.S. Pat. nos. 2,846,408;3,914,188;4,205,136;5,064,872 5,674,918;6,346,205;9,650,466 and U.S. patent application Ser. No. 2013/0251980, each of which is incorporated herein by reference. Useful polyurethane and polyisocyanurate rigid foams may include those available from Foam Products Corporation of san dieyi, missouri. Examples of other useful foams include, for example, polyimide foams (such as described by U.S. patent No. 6,956,066) and PVC-methacrylate crosslinked foams (such as described in U.S. patent No. 7,879,922), each of which is incorporated herein by reference.
The thermoset foamed polymer attached to or integral with the article may be of any useful depth, such as the entire thickness of the image receiving layer 40 or skin described above. Likewise, if the image is formed directly on and within a thermoset polymer foam with or without a skin, the image depth may be any useful depth and may be equivalent to the depth described above for the thickness of the image receptive layer.
Since thermoset foams have been found to be useful in forming dye sublimation images attached thereto or integrally formed therein, the articles can have a tunable thermal conductivity to achieve improved comfort and heating in a sunny environment as compared to commercial plastic composite decks, more similar to wood decks. For example, the article may have a thermal conductivity of up to about 1W/mK, 0.5W/mK, 0.25W/mK, 0.1W/mK to 0.001W/mK according to ASTM C518-15.
The article may also have tunable and desirable structural or insulating properties due to the ability to equiaxed or anisometric bond different reinforcing components and to varying thermoset and thermoset foam types and foam densities and foam morphology structures. This allows tuning the article for different uses. For example, the flexural strength of the article may vary from 250psi or 500psi to 10,000psi or 20,000psi according to ASTM-D143, and the article density may vary over a wide useful range for construction applications, with particular advantages in light weight as compared to composite plastic panels. For example, the article may have an apparent density of 0.01g/cc, 0.1g/cc to about 1.5g/cc, 1.2g/cc, 1g/cc, 0.9g/cc, 0.75g/cc, or 0.5 g/cc. The density may be determined by determining the dimensional volume and weight or by using archimedes' principle.
Illustratively, the dye sublimation images may be formed by any suitable dye sublimation method (such as those known in the art). In many cases, it has been found that in order to achieve the desired definition of the image and to avoid blistering and puncturing of the dye sublimation image, the thermoset polymer, at least a portion of which is foam ("thermoset foam"), is heat treated prior to forming the dye sublimation image. The temperature is desirably that which stabilizes the image receiving layer 40, which may be integral skin or coated onto a thermoset polymer foam, as described above. Such a stabilization temperature is typically a temperature that does not cause the image to be formed to foam, degrade, or fail when the image receiving layer 40 is exposed to dye sublimation conditions. Typically, the stabilization temperature is within 25 ℃,20 ℃,10 ℃, of the temperature used to form the dye sublimation image, which is typically about 150 ℃ or 170 ℃ to about 200 ℃ or 225 ℃. Desirably, the stabilization temperature is above the dye sublimation temperature.
The time at the stabilization temperature may be any time sufficient to stabilize the image-receiving layer, as described above. The time may be, for example, 1 or 2 minutes to 1 or 2 hours. The atmosphere may be any useful atmosphere, such as air or an inert atmosphere at any useful pressure, including atmospheric pressure or vacuum.
If it is desired to adhere or attach a separate layer to the thermoset foam when forming the article, such a layer may be attached or attached to the thermoset polymer by any suitable method. For example, the adjoining layer 30 and the image receiving layer may be formed by laminating a film thereto and applied by brush coating, spray coating, doctor blade coating, screen printing, or the like. Illustratively, the layer may be formed by coating a thermoset polymer foam with an emulsion, liquid polymer, or dispersion in one or two parts (reactive coatings) and curing on the thermoset foam. Curing may simply allow the film to coalesce and form a continuous film, or may allow a two part system to react and cure into a layer on the thermoset foam. Once the layer has cured or the liquid medium has evaporated or removed, the layer and thermoset polymer foam may be stabilized, as described above.
Dye sublimation images may be formed by any suitable method or apparatus, such as those known in the art. Examples include methods and apparatus described in the following patents: international patent application number WO2020210700, U.S. patent number 4059471;4664672;5,580,410;6,335,749;6,814,831;7,033,973;8,182,903;8,283,290;8,308,891;8,561,534;8,562,777;9,956,814; and 10,583,686, U.S. patent application Ser. No. 2002/148054;2003/019213 and 2020/0346483, and Canadian patent No. 2,670,225, each of which is incorporated herein by reference. The method may employ any suitable dye sublimation ink, such as those known in the art. Examples of dye sublimation inks include those described in the following patents: U.S. patent No. 3,508,492;3,632,291;3,703,143;3,829,286;3,877,964;3,961,965;4,121,897;4,354,851;4,587,155, european patent No. 0098506 and International patent application WO2018208521, each of which is incorporated herein by reference. Likewise, the transfer sheet may be any suitable transfer sheet, such as those known in the art and described in the references cited in this paragraph. In general, a conventional paper transfer sheet can be used.
Dye sublimation is typically conducted at a dye sublimation temperature of about 150 ℃ or 170 ℃ to about 200 ℃ or 225 ℃ for a dye sublimation time sufficient to migrate and become incorporated into the image-receiving layer to a desired depth, and may vary depending on the application (e.g., the desired depth to achieve a desired wear life). Typically, the dye sublimation time is 30 seconds, 1 minute, 2 minutes, or 5 minutes to about 30 minutes, 20 minutes, or about 15 minutes. The pressure may be any available pressure to effectively transfer the image at the desired time and detail without deforming and compacting the thermoset polymer foam. In general, it is desirable that the pressure be as small and uniformly applied as possible to achieve a uniform and consistent dye sublimation image in a layer attached to or integral with the thermoset polymer foam. The pressure may be applied uniaxially or equiaxed. The pressure may be applied by using a vacuum press, and the pressure may be increased by applying an external air pressure higher than the atmospheric pressure. The pressure may be about 1psi, 2psi, 5psi to about 300psi, 150psi, 100psi, 50psi, 20psi, or 15psi.
Surprisingly, the method can use thermoset polymer foams having degradation temperatures near the temperature at which dye sublimation occurs (e.g., within about 10 ℃). In embodiments, the thermoset polymer foam may be a polyurethane foam having closed cells or open cells as described above, and the foam has a purified water or cementitious reinforcing component. Cementing refers to the setting or formation of a bond of particles by hydration or carbonation. Examples of useful reinforcement components include portland cement, coal ash, lime, slaked lime, lime mortar, magnesia, clay minerals (kaolinite, montmorillonite, vermiculite, dickite, halloysite, attapulgite, etc.), silica gel, or mixtures thereof. For example, the load may be at least about 30%, 40% or 50% to about 90%, 85% or 80% by weight of the reinforcement and foam, and the size and morphology may be as described above. Without being limited in any way, it is believed that these types of reinforcements help to maintain the structural integrity of the foam under dye sublimation conditions, and may also advantageously adsorb or absorb any decomposition products of the foam, which may enhance the secondary structure, thereby facilitating preserving the mechanical integrity of the thermoset foam and avoiding damage to the dye sublimation image.
The articles of the present invention may be used in any application where the desired aesthetic article is exposed to weathering, whether due to abrasive wear, rain (e.g., acid rain), or exposure to electromagnetic radiation (such as electromagnetic radiation from the sun). Particularly useful applications for the articles of the present invention include those that traditionally use natural lumber. For example, the article may be a panel, siding shingle, door, deck, roof shingle, fence post, rail, armrest, panel, furniture, veneer, handle, or frame.
Illustrative embodiments
The following examples are provided to illustrate articles and methods of forming the same, but are not intended to limit the scope thereof. All parts and percentages are by weight unless otherwise indicated. Table 1 shows the components used in the examples and comparative examples.
Example 1
Polyurethane rigid foam, similar to the rigid foam example described in U.S. patent No. 9,956,814 and having a fly ash reinforcing component of greater than about 50% by weight, is sanded to expose foam cells and smooth the surface. A layer is formed on the surface of the polyurethane foam by coating the surface with an aqueous polyurea dispersion obtained from ASTC Polymers of san ana, california under the trade name 5500 aliphatic polyaspartic acid polyurea. The coating forms a uniform layer (image receiving layer) having a thickness of about 250 microns. The coated polyurethane foam is pre-treated in air to about 200 ℃ for about 10 to 20 minutes to further cure the coating and pre-treat the polyurethane foam.
A dye-sublimation image transfer sheet was formed by printing an image onto paper Jetcol HTR 1000 from Neenah Coldenhove Performance Materials of elbeck, netherlands using dye-sublimation ink obtained from Sawgrass Technologies of miscanthus, south carolina.
A thermal transfer sheet having an image is placed on the coated pretreated polyurethane foam. The image was transferred by heating to about 200 ℃ and uniaxial pressing using a Hotronix hot press (Carmichaels, PA) at a pressure of about 10 to 40psi for about half a minute to two minutes. The sharpness of the image transfer is good and the layer with the dye sublimation image is not damaged. The dye sublimation image penetrates substantially the entire thickness of the image receptive layer.
Example 2
Rigid polyurethane marine panels having densities of 20 to 26 pounds per cubic foot are available from Polyumac in sea early, florida, U.S. A layer, pretreatment and dye sublimation image were formed in the same manner as in example 1. The sharpness of the image transfer is good and the layer with the dye sublimation image is not damaged. The dye sublimation image penetrates substantially the entire thickness of the image receptive layer.
Example 3
The same rigid polyurethane foam as in example 2 was prepared in the same manner. The polyurethane foam after sanding is pre-treated in air to a pre-treatment temperature of about 180 to 200 ℃ for about 10 to 20 minutes. An industrial polyurethane powder image receptive layer is deposited on the sanded polyurethane foam and cured at a curing temperature of 175 to 200 ℃. Dye sublimation images were formed using a vacuum press at temperatures of 175 to 200 ℃ for 1 to 10 minutes in a similar manner as described in U.S. patent No. 7,033,973. The transferred image is transferred with good definition and without damaging the dye sublimation image. The dye sublimation image penetrates substantially the entire thickness of the image receptive layer and an example of an article formed therefrom is shown in fig. 2.
Comparative example 1
Example 3 was repeated except that no pretreatment of the foam was performed. The transferred image is damaged and shows a bubbling puncture point or the like. The dye sublimation image penetrates substantially the entire thickness of the image receptive layer.